It's not new by any means, but it's a great place to hear airchecks from every era, from the 50s to the 2000s and beyond. It's a Facebook site called "Sharing Airchecks" and that's exactly what it's devoted to. It's not private and is accessible to anyone who wants to hear what radio sounded like in various era.  

No one will ever beat Dale Patterson's "Rock Radio Scrapbook" as the repository for audio greatness, but this is another source where contributors celebrate all eras of the medium. And it's worth a visit. 

Sharing Airchecks